Estimating turbulent boundary layer characteristics by high-speed infrared thermography

Abstract

We propose a new methodology for the quantitative analysis of fluid boundary layers based on high-speed thermographic measurements. The methodology is tested on a boundary-layer flow formed by a single submerged round jet impinging on an infrared-transparent flat plate. We calculate the power spectra of fluctuations in thermal radiation recorded from a thin near-wall boundary layer for a wide range of initial flow parameters. The results show that changes in power spectra scaling can be directly related to the transitions in a flow pattern within the boundary layer.